Images of this find were sent to Trevor Parker of the Ordnance Society. He confirmed that these three shell cases belong to a six-pounder Hotchkiss gun. This particular type of gun was introduced in 1884 for use against torpedo boats. They were used during First World War on the Arethusa and early 'C' class cruisers and a few submarines as well as on Monitors M.15 through M.33. Originally French in origin, they were introduced to Britain in 1886 (Tucker 2013). Many were subsequently used as sub-calibre and saluting guns which meant that they were still available in 1939 (Naval Weapons, Naval Technology and Naval reunions webpage, accessed September 2017). Although these cartridges are empty, there is a good chance that their primers are live.The evidence for this is that they all have their primer protectors in place.These are three-legged covers that clip over the base and have a domed area in the middle that sits over the primer in the middle of the case bottom, to prevent accidental striking of the primer before it's loaded (War Office 2003). The edges of these clips are visible on all three cases and would have been removed before firing. This raises the question of where the shells have gone if they were not fired. The shells would have been held firmly in place therefore it has been suggested that these shell cases are of some age, dating back to the early 1900s, shortly after this type of gun appeared and that the actual shells have rusted away completely. Images of this find were sent to Trevor Parker of the Ordnance Society. He confirmed that these three shell cases belong to a six-pounder Hotchkiss gun. This particular type of gun was introduced in 1884 for use against torpedo boats. They were used during First World War on the Arethusa and early 'C' class cruisers and a few submarines as well as on Monitors M.15 through M.33. Originally French in origin, they were introduced to Britain in 1886 (Tucker 2013). Many were subsequently used as sub-calibre and saluting guns which meant that they were still available in 1939 (Naval Weapons, Naval Technology and Naval reunions webpage, accessed September 2017). Although these cartridges are empty, there is a good chance that their primers are live.The evidence for this is that they all have their primer protectors in place.These are three-legged covers that clip over the base and have a domed area in the middle that sits over the primer in the middle of the case bottom, to prevent accidental striking of the primer before it's loaded (War Office 2003). The edges of these clips are visible on all three cases and would have been removed before firing. This raises the question of where the shells have gone if they were not fired. The shells would have been held firmly in place therefore it has been suggested that these shell cases are of some age, dating back to the early 1900s, shortly after this type of gun appeared and that the actual shells have rusted away completely. These items were recovered from the wreck of SS Unity, a British transport steamship built in 1902 by Murdoch & Murray, Glasgow. On 2 May 1918, whilst on a voyage from Newhaven to Calais with a cargo of ordnance, SS Unity was sunk by the German submarine UB57, with the loss of 12 lives. NRHE and Kent HER reference numbers cited in this record refer to the wreck of SS Unity. The location of SS Unity was taken from the British National Grid co-ordinate from the National Record of the Historic Environment. A RDF representation of MAS-D100115 2017-09-08T08:39:56+01:00 2017-10-05T11:37:37+01:00 MAS-D100115 MAS-D100115 GB en-GB The Trustees of the British Museum The Trustees of the British Museum 1 The period from for the object http://purl.org/NET/Claros/vocab#Thumbnail Attribute as courtesy of the British Museum A thumbnail image of MAS-D100115 With finder MAS Created by MAS Mr Trevor Parker Mr Trevor Parker Identified by Mr Trevor Parker V L Identified by V L Copper alloy Primary material of object Complete 340. Length By Attribution 3.0 Attribute as courtesy of the British Museum A full resolution image of MAS-D100115 Classification of object